System of Environmental-Economic Accounting

Biophysical Modelling (Levels 1 and 2)

Project: Advancing the SEEA

Experimental Ecosystem Accounting

System of Environmental-Economic Accounting

Contents

Beginner level (level 1) • Learning objectives

• Presentation

• Exercise sheet

• Answer sheet

Intermediate level (level 2) • Learning objectives

• Presentation

• Exercise sheet

• Answer sheet

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System of Environmental-Economic Accounting

Level 1: Learning Objectives

Understand the spatial units used in Ecosystem

Accounting and the role of biophysical modelling

in support of Ecosystem Accounting • Spatial Units

• The role of spatial and of temporal modelling

Required prior knowledge: the concept of

ecosystem services

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System of Environmental-Economic Accounting

The three spatial Units in Ecosystem Accounts

Ecosystem Accounting

Unit (EAU) = a country,

province or watershed

Land cover/ecosystem

functional unit (LCEU) =

e.g. Deciduous forest

Basic Spatial Unit = a grid

cell / pixel

Ecosystem services flow,

ecosystem condition and

ecosystem asset needs to

be defined for every pixel

individually (i.e. mapped)

Land cover map of Area X

Scale: 1:50,000

Deciduous forest

Pine forest

System of Environmental-Economic Accounting

Biophysical modelling

Biophysical modelling for the purpose of

ecosystem accounting is required to: • Capture the spatial variability of ecosystems

• Capture the temporal variability of ecosystems

Modelling: make it as simple as possible, but not

simpler (after Einstein)

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System of Environmental-Economic Accounting

Spatial variability in Ecosystems

Ecosystems vary across space because of

differences in altitude, soils, vegetation, climate,

etc. and because of spatial differences in the

management of ecosystems (e.g. as a function

of distance to road or settlement)

The Wetland ecosystem ‘De Wieden’, the

Netherlands consists of different zones with

different vegetation, humidity, soils, etc.

(Source: Hein et al., 2006)

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System of Environmental-Economic Accounting

Modelling spatial variability

Modelling spatial variability is required because • ecosystem accounting aims to record flows of

ecosystems and stocks of ecosystem capital; and

• both flows and stocks can be spatially very

heterogeneous.

Flows and stock modelling usually requires the

combination of spatial datasets (maps) and

point-data(e.g. from surveys).

To combine these datasets, and to understand

ecosystem flows and assets in areas with no

data, a spatial model can be deployed.

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System of Environmental-Economic Accounting

Modelling temporal variability

Temporal models are required to analyse ecosystem assets

The Net Present Value of an ecosystem asset is the sum of

the net, current and discounted future values generated by

the ecosystem

These values depend upon the capacity of the ecosystem to

regenerate, for instance the regrowth of the forest after

harvesting.

Temporal models reveal the regeneration/regrowth of the

ecosystem

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The increase in a biological

resource often follows an S-curve,

where growth levels approach

zero of at the carrying capacity.

System of Environmental-Economic Accounting

Exercise 1

What are the three spatial units in Ecosystem

Accounting, and what is their meaning ?

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System of Environmental-Economic Accounting

Exercise 2

Which processes or factors determine changes

in the stock of a (renewable) ecosystem asset,

for instance a timber resource in a natural

forest?

Which of these factors requires temporal

modelling in order to analyse it?

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System of Environmental-Economic Accounting

Level 2. Biophysical modelling

Learning objective: • To understand which types of modelling approaches

can be used for the spatial and temporal modelling of

ecosystem services in an accounting context

Prior knowledge • Biophysical modelling level 1

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System of Environmental-Economic Accounting

Spatial modelling

Useful to estimate ecosystem services flows and

ecosystem assets across spatial units in the

landscape

In spatial models: ecosystem condition

indicators, ecosystem services flow and

ecosystem assets are defined and analysed for

each spatial unit

This requires Geographical Information

Systems, where the spatial unit is usually a pixel

(i.e. a grid cell in a grid, with specific x and y

coordinates) 14

System of Environmental-Economic Accounting

Four types of spatial models

Look-up tables: specific values for an ecosystem service or other variable are attributed to every pixel in a certain class, usually a land cover class.

Statistical approaches: relate ecosystem services flow, asset or condition to explanatory variables such as soils, land cover, climate, distance from a road, etc., using a statistical relation derived from survey data.

Geostatistical interpolation: techniques such as kriging rely on statistical algorithms to predict the value of un-sampled pixels on the basis of nearby pixels in combination with other characteristics of the pixel.

Process based modeling: involves predicting ecosystem services flows based on a set of environmental properties, management variables and/or other spatial data sources, based on modelling of the ecological and/or ecosystem management processes involved.

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System of Environmental-Economic Accounting

Ecosystem services Central Kalimantan Carbon storage Model used

Look Up Tables (every land cover class is attributed a specific carbon storage value) Kriging (values are interpolated from samples)

High : 1.67 m3/ha/year

Low : 0.42 m3/ha/year

Timber production

Source: Sumarga and Hein, 2014

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System of Environmental-Economic Accounting

Ecosystem services Central Kalimantan

Orangutan habitat Model used:

Statistical model (Maxent) (habitat suitability predicted on the basis of forest cover, distance from road, etc.) Process-based Model (primary ecosystem production minus soil respiration)

High : 8.52 ton/ha/year

Low : -23.22 ton/ha/year

Carbon sequestration

Source: Sumarga and Hein, 2014 17

System of Environmental-Economic Accounting

Modelling ecosystem services

Can be done in stand-alone GIS packages such

as ArcGIS or Q-GIS (freeware) or

Modelling packages such as ARIES or InVEST

Advantages of ARIES and InVEST is that some

modules are pre-defined;

Advantage of standard packages is that they are

fully flexible and not dependent upon

(knowledge of) a specific modelling program

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System of Environmental-Economic Accounting

Question 1

Which four types of spatial models can be

distinguished?

What is the differences between them? Explain

in your own words.

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System of Environmental-Economic Accounting

Four types of spatial models

Look-up tables: specific values are attributed to every pixel in a

certain class, usually a land cover class.

Statistical approaches: ecosystem services flow, asset or condition

is related to explanatory variables such as soils, land cover, climate,

distance form a road, etc., using a statistical relation derived from

survey data.

Geostatistical interpolation: techniques such as kriging rely on

statistical algorithms to predict the value of un-sampled pixels on the

basis of nearby pixels in combination with other characteristics of

the pixel.

Process based modeling: involves predicting ecosystem services

flows based on modelling of the ecological and/or ecosystem

management processes involved.

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System of Environmental-Economic Accounting

Question 2

Select one or two ecosystem services relevant

for your case study area of interest • Which different sets of data are required to map this

service?

• How can these datasets be combined?

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System of Environmental-Economic Accounting

Level 2: Biophysical Modelling

References Hein, L., Van Koppen, K., De Groot, R. S., & Van Ierland, E. C. (2006). Spatial

scales, stakeholders and the valuation of ecosystem services. Ecological Economics,

57(2), 209-228.

Sumarga, E. And Hein, L., 2014. Mapping Ecosystem Services for Land Use

Planning, the Case of Central Kalimantan. Environmental management, pp. 1-14.

Further Information • SEEA Experimental Ecosystem Accounting (2012)

• SEEA-EEA Technical Guidance (forthcoming) ▫ Detailed supporting document on “Biophysical Modelling” by

Lars Hein

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System of Environmental-Economic Accounting

Evaluation of the training module

Please complete the evaluation form for this module

For this module

• What did you learn that you could apply in your work?

• Was the presentation clear and informative?

• Was it too simple? Too complex?

• Was there anything you did not understand?

• What additions or deletions would you suggest (recognizing that

the unit is intended for a general audience)?

• Do you have any suggestions as to how the SEEA-EEA may be

improved (concepts, principles) in this area?

System of Environmental-Economic Accounting

Acknowledgements

This project is a collaboration of The United Nations

Statistics Division, United Nations Environment

Programme and the Secretariat of the Convention on

Biological Diversity and is supported by the Government

of Norway.